Rainbow Electronics AT89C5122 - Manual (Page 122)

122
AT8xC5122/23
4202E–SCR–06/06
Reset Value = XXXX XXXXb
Reset Value = 0000 0000b
Table 71. USB FIFO Data Endpoint X (X=EPNUM set in UEPNUM Register) -
UEPDATX (S:CFh)
7 6 5 4 3 2 1 0
FDAT7 FDAT6 FDAT5 FDAT4 FDAT3 FDAT2 FDAT1 FDAT0
Bit
Number
Bit
Mnemonic Description
7 - 0 FDAT [7:0]
Endpoint X FIFO data
Data byte to be written to FIFO or data byte to be read from the FIFO, for the
Endpoint X (see EPNUM).
Table 72. USB Byte Count Register X (X=EPNUM set in UEPNUM Register) - UBYCTX
(S:E2h)
7 6 5 4 3 2 1 0
- BYCT6 BYCT5 BYCT4 BYCT3 BYCT2 BYCT1 BYCT0
Bit
Number
Bit
Mnemonic Description
7 -
Reserved
The value read from these bits is always 0. Do not change this bit.
6 - 0 BYCT[6:0]
Byte Count LSB
Least Significant Byte of the byte count of a received data packet. This byte count
is equal to the number of data bytes received after the Data PID.